Latest tests shows that livestock around the residence of five people, who recently died of bird flu in North Sumatra of Indonesia, were not contaminated by the avian influenza virus, a government official said here on Friday.

Indonesian Minister of Agriculture Anton Apriantono said that PCR (polymerase chain reaction) test, a final examination to determine whether the animals got infected with the virus, showed a negative result on pig, chicken and duck.

He said that his ministry would repeat the test on other samples from the same location.

"All the result (of the PCR test) are negative, but the investigation must be deepened," he said.

The World Health Organization (WHO) earlier confirmed that five people in North Sumatra province linked by blood and one from East Java province were positively infected by the highly pathogenic H5N1 virus.

The country's total number of fatality of bird flu now stood at 32 and that of infection at 43.

All over the world, the WHO has raised the confirmed human death toll from the H5N1 bird flu strain to 122, while the total number of confirmed human infections since the current outbreak began in 2003 has reached 216.

Source: Xinhua